The present invention relates in general to vacuum cleaning and more particularly concerns novel apparatus and techniques for effectively dislodging debris, especially in hard-to-reach locations, while reducing mechanical wear and being useable on a wide variety of surfaces, including rough surfaces.
Vacuum cleaners have been widely used for many years for household and industrial cleaning. More recently, larger machines have been introduced for street sweeping. A typical prior art vacuum cleaner may include passive or driven mechanical brushes in combination with suction for removing debris.
Nozzle construction typically is nothing more than a round tube, or a round tube that flares into an elongated opening. The nozzle may terminate in a brush or other structure for dislodging debris, and the brush may be independently driven. An operator then maneuvers the nozzle over the area to be cleaned. In systems typically used for cleaning streets, the nozzle may be located just above conventional street sweeping brushes. A disadvantage of using brushes is that brushes wear out relatively rapidly and may not be effectively used except over relatively smooth, flat surfaces, such as floors, streets and carpets.
These disadvantages result in prior art systems being marginally effective in cleaning areas such as railway tracks, curbstone areas, niches and other hard-to-reach areas.
Accordingly, it is an important object of the invention to provide improved vacuum cleaning apparatus and techniques that overcome one or more of the disadvantages set forth above.
It is another object of the invention to achieve the preceding object with apparatus that is relatively inexpensive to fabricate and effectively operated by relatively unskilled personnel.
It is a further object of the invention to achieve one or more of the preceding objects with apparatus that is relatively long wearing and suitable for use in cleaning a wide variety of areas, smooth, rough or hidden.
It is a further object of the invention to achieve one or more of the preceding objects with apparatus that uses not only suction but compressed air.
It is a further object of the invention to achieve one or more of the preceding objects with apparatus arranged to provide relatively little friction between the nozzle and the surface cleaned to make cleaning relatively easy.